Process or method of making cutters.



E. LURKER.

PROCESS 0R METHOD OF MAKING CUTIERS.

APPLICATION FILED FEB. 11- I918.

PatentedSeptS, 1918.

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Patented. Sept. 3, 1918.

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RDWARDLURKER, 0F KOKOMO, INDIANA, ASSIGNOR TO THE HAYNES STELLITE CO., OF KOKOMO, INDIANA.

PROCESS 01!. METHOD OF MAKING CUTTERS.

Specification of Letters Patent.

Patented Sept. 3, 1918.

Original application filed November 24, 1917, Serial No. 203,761. Divided and this application filed February 11, 1918. Serial No. 216,495.

To all whom it may concern:

Be it known that I, EDWARD LURKER, a citizen of the United States, residing at Kokomo, county of Howard, State of Indiana, have invented certain new and) useful Improvements in Processes or Methods of Making Cutters, of which the following is a specification.

Thisinvention relates to improvements in process or method of making cutters.

My present application is a division of my application for Letters Patent filed November 24, 1917, Serial No. 203,761, claims to the product being retained in that case.

The main object of this invention is to provide an improved rocess or method of making cutters by w ich a very superior article results, no tempering or hardening of the blades being required after' the cutter is formed.

Further objects, and objects relating to structural details, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification. The invention is clearly defined and pointed out in the claims.

A milling cutter and the steps or means for carrying out my invention ,is clearly illustrated in the accompanying drawingforming a part ofthis specification, in which:

Figure I isa perspective view of a milling cutter manufactured by my improved process.

Fig. II is a perspective view of the drag of the mold employed by me in the manufacture of the milling cutter shown in Fig. I.

Fig. III is a perspective view of the intermediate part of the mold or lower part of the cope. v

. Fig. IV is an inverted perspeotiveview of the to portion of the cope.-

Fig. V is a perspective vlew of the drag and the intermediate portion of the mold assembled with the cutter blades positioned therein.

Fig. VI is a rear perspective view of one of the bladespreferably employed by me.

Fig. VII is a-more or less conventional side elevationof the means which I employ for rotating the mold during the casting operation.

. fusing point of such metals.

In the drawing, similar reference characters refer to similar parts throughout the several views.

In carrying out my improved process or method I employ blades of special alloys of cobalt and metals of the chromium group known commercially under thetrade name stellite and more particularly described in Letters Patent to Elwood Haynes No. 873,745, ,dated December 17 1907, No. 1,057,423 and No. 1,057,828, dated April 1, 19%3fand No. 1,150,113, dated August 17, 19 5.

The body'is preferably formed of nickel steel alloy although other steels and other alloys may be used with uite satisfactory results. Gutter blades made from stellite may be worked at considerably higher speed and have greater cutting ualities and are more durable than any igh speed steel known to the applicant. Further, on account of the high fusing point of the stellite the body may be cast thereon-without the blades being afl'ected in any manner by the resulting heat, that is, the blades are not annealed or their temper is not drawn or affected in any manner. The fusing or annealing point of the blades is higher than the pouring temperature of steels such as nickel steel, tool steels, and various relatively high grade metal alloys which might be employed for the body. In other words, the setting point of stellite is above the The body when formed of nickel steel and other high grade metal is tough and elastic o that it is capable of withstanding very severe shocks and strains and further in cooling shrinks evenly upon the blades so that they are securely united Land effectively supported and retained.

I also preferably employ means for bringing the body metal at pouring temperature into intimate contact with the blades before it has appreciably cooled or chilled, thus insuring a good contact of the. body with the blades. Referring to the drawing, the cutter illustrated in Fig. I is the type known as a side milling cutter. It will be understood that my invention is adapted to the manufacture of other forms of milling cutters and cutting tools.

The body 1 is, as stated, preferably formed 'erably formed of stellite.

the blades 3. wedgeshaped projections 12 which form the beveled sides or blade supporting or abutment parts 5 of the body. The mold mem-.

of nickel steel alloy, although other metals may be employed with quite satisfactory results. The body 1 has a bore 2 for the shaft or arbor. The blades 3 are, asstated, pref- These blades are preferably outwardly tapered and. their rear faces are preferably provided with diagonally crossed ribs 4, as shown in Fig.- VI. When the body is cast upon the blades the wedge shape of the blades and these ribsform a very secure joint between the body and the blades, the body shrinking upon the blades so that they are effectively clamped thereby.

The portions 5 of the body between the blades which serve as'supporting abutments therefor are beveled toward the rear from the rear side 6 of one of the blades to the front side 7 of the succeeding blade. This provides proper clearance for the blades and also permits easy sharpening or grinding thereof.

In the manufacture of the cutter illustrated' I provide a three part mold com prising a drag member 8, an annular cope or intermediate member 9, and a top cope member 10. The drag member is provided with shallow grooves 11 adapted to receive Between the grooves are her 9 is provided with groove-like recesses 13 adapted to receive the ends of the blades alined with the grooves 11 of the drag. The projections 14 between the recesses 13 form the beveled top or peripheral portions of the blade abutments 5.

The upper part 10 of the cope is similar to't'he drag, beingprovided with grooves 11' and projections 12 opposed to those of the drag. The top part of the cope is provided with a central sprue 15. The mold parts are assembled wit-h the blades inserted or supported therein in the position which they occupy in the cutter. The body metal is then poured into the mold and I prefer at the same time to rotate the mold which insures that the metal is forced out of the periphery of the mold and into intimate contact with the several blades before the metal is materially chilled or cooled.

As a convenient means for accomplishing this the mold parts are clamped together by means of the clamping rings 16 and bolts 17,see Fig. VII.

In Fig. VII I show a means for rotating the mold comprising the frame 18 support ing a vertical shaft 19 on which the flask may be mounted. This vertical shaft 19 is connected to the driving shaft 20 by the beveled gear 21. The motor 22 is shown furnishing power for the driving shaft. The molten metal is poured into the mold and by the centrifugal actiondriven or carried outwardly to the periphery of the mold into intimate contact with the blades before the metal has materially cooled or chilled.

As the blades are not afiected by the fusing temperature of the body no re-tempering is required and the body may be allowed to cool normallyso that it is not distorted or undue stresses caused therein as might occur 'if the cooling was hastened. This natural cooling of'the body permits it to shrink upon the blades evenly and owing to this shrinking action and to the tapered form of the blades and the ribs thereon the blades are very firmly retained and supported. In fact,

1. The process of forming rotary cutters comprising arranging outwardly tapered cutter blades of stellite having ribs on one si'de in a mold in the position occupied thereby in the cutter and with their inner ends projecting into said body cavity of the mold, pouring a body of molten steel and rotating the mold sothat the molten steel is subjected to centrifugal force and brought into intimate contact with the cutter blades before appreciably cooling, the annealing point of the blades being above the pouring temper? ature of the body.

2. The process of forming rotary cutters comprising arranging outwardly tapered cutter blades of stellite in a 'mold in the position occupied thereby in the cutter and with their inner ends projecting into said body cavity of the mold, pouring a body of molten steel and rotating the mold so that the molten steel is subjected to centrifugal force and brought into intimate contact with the cutter blades before appreciably cooling, the annealing point of the blades being above the pouring temperature of the body. I

3. The process of forming cutters comprising arranging a cutter blade of stel lite in a mold with a portion thereof proprising arranging cutter blades of stellite having transversely disposed ribs.

thereon of substantial cross section in a mold in the position occupied thereby in the cutter and with their inner ends projecting into the body cavity of'the mold, and-pouring abody of molten metal, the fusing point of the blades being above the pouring temperature of the body so that the blades are not fused thereby, but are embedded.

5. The process for forming cutters comprising arranging cutter blades of stellite in the periphery of a mold in the position occupied thereby in the cutter and with their inner ends projecting into the body cavity of the mold and pouring a body of metal, the fusing or annealing point of the blades being above the pouring point of the body.

6. The process of forming cutters comprising arranging outwardly tapered cutter blades having diagonally disposed crossed ribs of substantial cross section on one side in a mold in the position occupied thereby in the cutter and With their inner ends projecting into the body cavity of the mold, and pouring a body, the fusing point of the blades being above the pouring point of the body so that the ribs are embedded in the body and not fused therewith.

7. The process for forming cutters comprising arranging cutter blades of stellite in the periphery of a mold in the position occupied thereby in the cutter and with their inner ends projecting into the body cavity of the mold and pouring a body of nickel steel, the fusing or annealing point of'the blades being above the pouring point of the bod Iii witness whereof I have hereunto set my hand and sealin the presence of two witnesses.

EDWARD LURKER. [1,. s.]

Witnesses: .F. C. James,

ALLEN SHELDON. 

